Post-operatively, gastrointestinal functions usually deteriorate. The causes of this deterioration are varied and include such factors as the use of anesthesia or pain killing drugs, and the manipulation of the bowel during the operation. Additionally, air swallowed by the patient contributes to gastrointestinal malfunctions since the gas is inefficiently propelled through the digestive tract. This causes a problem commonly known as abdominal distention which not only impairs bowel function and interferes with the rate of absorption of nutrients through the bowel, but often prevents the patient from breathing deeply or coughing, which can lead to severe pulmonary difficulties. In severe cases, the pressure caused by the abdominal distention has been known to break open the patient's wound. One of the indirect effects of abdominal distention is the fact that due to the pain associated with it, and the lesser rate of bowel absorption, the patient often becomes undernourished which slows the healing process. It has, therefore, been a long-standing objective of the medical profession to prevent abdominal distention while providing sufficient nutrition in order to speed the patient's recovery.
U.S. Pat. No. 4,543,089 to Moss, incorporated herein by reference, discloses a gastrointestinal aspirating and feeding device which is designed to effectively eliminate abdominal distention while simultaneously providing a patient with sufficient nutrition. The gastrointestinal aspirating and feeding device generally includes a tube having a feeding lumen and an aspirating lumen which are inserted gastrally into a patient. Preferably, the aspirating lumen includes a plurality of aspirating orifices, and the feeding lumen includes an orifice positioned adjacent a distal end of the tube.
Upon proper insertion of the gastrointestinal aspirating and feeding device into the body of a patient, the feeding orifice is disposed in the proximal duodenum. Upstream from the feeding orifice, a first set of aspirating orifices is positioned within the terminal portion of the stomach, the pylorus and/or the proximal duodenum. In addition, further upstream from the first set of aspirating orifices, a second set of aspirating orifices is positioned within the main body of the stomach.
U.S. Pat. No. 4,642,092 to Moss, incorporated herein by reference, again discloses a gastrointestinal aspirating and feeding device which is designed to effectively eliminate abdominal distention while simultaneously providing a patient with sufficient nutrition. As in the '089 patent to Moss, the gastrointestinal aspirating and feeding device includes a tube having a feeding lumen and an aspirating lumen. The aspirating lumen includes a set of primary aspirating orifices and a set of secondary aspirating orifices, and the feeding lumen includes an orifice positioned adjacent a distal end of the tube. The primary aspirating orifices function as main aspirating sites, while the secondary aspirating orifices act as suction breakers for the primary aspirating orifices. At predetermined points along the tube, there are placed a pair of aspirating orifices, each pair including a primary aspirating orifice and a secondary aspirating orifice.
When the gastrointestinal aspirating and feeding device disclosed in Moss '092 is surgically inserted within a patient's body, the feeding orifice is positioned in the proximal duodenum. Further, at least one pair of primary and secondary aspirating orifices are positioned within the terminal portion of the stomach, the pylorus and/or the proximal duodenum, and at least one pair of primary and secondary aspirating orifices are located within the main body of the stomach.
The gastrointestinal aspirating and feeding devices illustrated in Moss '089 and Moss '092 effectively remove swallowed air from the digestive system during surgery, and provide the digestive system with liquid nourishment immediately after surgery, without overfeeding. Advantageously, overfeeding in an average size patient is prevented by separating the feeding orifice a fixed distance of approximately three inches from the closest aspirating orifice. Such a separation allows the digestive system of an average size patient to absorb the maximum amount of nourishment it can handle, while aspirating any amount of overfeeding before the functioning of the digestive system is compromised. Specifically, peristaltic activity along about 3 inches (7-8 cm) of intestine prevents spontaneous retrograde flow, acting in effect as a "one-way valve". When feeding rates are not excessive to the patient's gastrointestinal function, the three inch separation between the feeding orifice and the closest aspirating orifice prevents inadvertent loss of nourishment. However, should the patient be overfed, only the excess will flow retrograde with a virtually unmeasurable pressure increase within the system and be withdrawn through the aspirating orifice.
Unfortunately, although the gastrointestinal aspirating and feeding devices disclosed in Moss '089 and Moss '092 may be adequately employed for any size patient, the devices do not allow the surgeon to precisely control the distal extent of aspiration according to the size of the patient, especially for those patients having very small stomachs because of age or gastric resection. Further, the fixed three inch distance between the feeding orifice and the closest aspirating orifice may prevent the surgeon from optimally controlling the removal of excess liquid nutrients from those patients having above-average or below-average sizes, potentially resulting in an undesirable overfeeding or underfeeding condition.